Portable heating for small quantities of consumer product

ABSTRACT

An apparatus for heating a product includes a storage compartment for a product to be heated and a heater module physically and thermally coupled to the storage compartment. The heater module has a housing that defines a reaction chamber. A rigid barrier is inside the reaction chamber and defines first and second portions thereof. A first reactant is inside the reaction chamber, and a flexible bag (with a second reactant) is in the first portion of the first chemical reactant. The first and second reactants react exothermically upon contact. A piercing element can pierce the flexible bag. After piercing, the a fluid path and one or more fluid channels carry the second reactant to a section of the first portion of the reaction chamber away from where the flexible bag is located.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of priority to U.S. ProvisionalPatent Application No. 62/248,057, filed on Oct. 29, 2015 and entitledPortable Heating for Small Quantities of Consumer Product. Thedisclosure of the prior application is incorporated by reference hereinin its entirety.

FIELD OF THE INVENTION

This disclosure relates to a portable heater and, more particularly,relates to a portable heater for small quantities of consumer product.

BACKGROUND

A need exists for a safe system for anywhere heating of small consumerproducts. Examples of such applications are heating of nacho dip,dessert toppings, and heating of glues and sealants in cold weather.

SUMMARY OF THE INVENTION

In some aspects, an apparatus is disclosed for heating a productincludes a storage compartment for a product to be heated and a heatermodule physically and thermally coupled to the storage compartment. Theheater module has a housing that defines a reaction chamber. A rigidbarrier is inside the reaction chamber and defines first and secondportions thereof. A first reactant is inside the reaction chamber, and aflexible bag (with a second reactant) is in the first portion of thefirst chemical reactant. The first and second reactants reactexothermically upon contact. A piercing element can pierce the flexiblebag. After piercing, the a fluid path and one or more fluid channelscarry the second reactant to a section of the first portion of thereaction chamber away from where the flexible bag is located.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic, cross-sectional view of an exemplary portable,self-heating food contain

FIG. 2 is a schematic, cross-sectional view of a container design thatdetails one possible way of implementing self-heating in a containerlike the one in FIG. 1.

FIG. 3 is a schematic, cross-sectional view of a container design thatdetails another way of implementing the self-heating in a container likethe one in FIG. 1.

FIG. 4 is a close-up view showing part of the FIG. 3 container.

FIG. 5 is a close-up view showing part of the FIG. 3 container, with itspiercing element having pierced the inner flexible bag.

FIG. 6 is a close-up view of yet another container design that issimilar to the container design in FIG. 3, but includes an alternativepiercing element configuration.

FIG. 7 is a perspective, partial cut-away view of an exemplarydistribution manifold that may define fluid communication paths for theliquid chemical reactant to flow in a container like the one in FIG. 3.

FIG. 8A is an exploded view showing part of an alternative heater modulearrangement.

FIG. 8B is an exploded view showing part of another alternative heatermodule arrangement.

FIG. 9 is a graph showing temperature over time of a heater and aproduct being heated.

Like reference characters refer to like elements.

DETAILED DESCRIPTION

In some implementations, the systems and/or methods described herein arebased on the interchange of heat between two masses by conduction acrossa common interface, so that the two masses tend toward the sametemperature. In a typical implementation, one mass (i.e., a heater)would be heated in a short period of time to a maximum temperature andthen allowed to cool by transferring a portion of its heat to a targetmaterial (e.g., a food or other substance to be heated). The length oftime during which the product may need to be heated by this means toreach a desired temperature can depend on a variety of factorsincluding, for example, the product's viscosity, heat capacity, andthermal conductivity. If the hot mass (i.e., the heater) were designedto never exceed a chosen maximum temperature then the system could beused in virtually any condition of reasonable use without a significantrisk of injury. It remains, however, to provide the hot mass on demand.

In certain implementations, the heater may be configured to produce heatby initiating a chemical reaction between a potassium permanganatesolution and a glycerine-water solution. Moreover, this heating mayinvolve heating of liquid masses by the reaction of potassiumpermanganate and glycerine in water. The final temperature of the watersolution after completion of the reaction is generally governed by theconcentration of the two chemicals in the reaction. The presentapplication, which employs the reactants above as one choice but canemploy other heat producing reactions as well, describes the arrangementand activation of a heater appropriate for the purposes cited above.

FIG. 1 is a schematic, cross-sectional view of an exemplary portable,self-heating food container 100.

The illustrated container 100 has a sealed food compartment 102containing food (e.g., cheese 106 and nachos. The nachos are not shownin the figure, but would generally be located in the space below thecheese 106, labeled “Nachos”), and a heater module 104. The heatermodule 104 is physically and thermally coupled to the food compartment102 by a common, heat transfer wall 105 between the heater module 104and the food compartment 102. The heater module 104 is configured togenerate heat when operated to heat and melt the cheese 106. In atypical implementation, the cheese, when heated will melt and drip downover, and coat, the nachos.

After heating and melting, the apparatus 100 can be turned upside down(relative to the configuration shown in FIG. 1), the seal 108 (aremovable cover) can be removed and the nachos, now coated with a warmor hot cheese can be enjoyed!

The heater module 104 is easy to operate. In the illustrated example,the heater module has an activation button 110. To initiate heating, aperson merely needs to depress the button 110 (in direction indicated bythe arrow “A”). A few moments later, heat begins to pass from the heatermodule 104 into the sealed food compartment 102 to heat and melt thecheese 106. In some implementations, the container 100 may be sold witha cover (not shown in the figure) over the activation button 110 thatneeds to be removed in order to access the button and initiate theheating.

Thus, in a typical implementation, the illustrated self-heatingcontainer provides a great snack—nachos with hot melted cheese—anywhere,anytime, quickly and conveniently.

FIG. 2 is a cross-sectional view of a container design 200 that detailsone way of implementing the self-heating container 100 of FIG. 1.Although the illustrated implementation can, in some instances, beeffective, there are drawbacks, many of which can be overcome byimplementing one or more concepts also described herein.

The illustrated apparatus 200 has a storage compartment 202 containingproduct to be heated (e.g., cheese 206 that will melt onto nachos). In atypical implementation, the material to be heated (in this case cheesedip) would be sealed inside the container by a removable seal (notshown).

A heater module 204 is physically and thermally coupled to the storagecompartment 202 and is configured to produce heat when activated forheating the cheese in the storage compartment 202.

The heater module 204 has a housing 207 that defines a reaction chamber.There is a first liquid chemical reactant 214 (e.g., potassiumpermanganate solution) inside the reaction chamber, and a flexiblecontainer 212 (e.g., a bag) inside the reaction chamber, and immersed inthe first liquid chemical reactant 214. There is a second liquidchemical reactant 216 (e.g., a glycerine solution) inside the flexiblecontainer 212. The second liquid reactant 216 is configured to reactexothermically with the first chemical reactant 214 upon contact.

The flexible container 212 is located between a heat transfer surface205 (for heat to flow from the heater module 204 to the storagecompartment 202) and a base 220 of the heater module 204.

A piercing element 218 (attached to an external activation button 210)is movable (in direction “A”) to pierce the flexible container 212 andto enable at least some of the second liquid chemical reactant 216 toexit the flexible container 212 and mix with the first liquid chemicalreactant 214. In a typical implementation, the activation button 210 hasa tamper resistant feature (not shown) and features (also not shown)that cause the activation button (and piercing element 218) to latch orlock in the “in position” so, once depressed (e.g., moved in thedirection of arrow “A”), it will remain in that position.

In some instances, the illustrated implementation can be somewhateffective. However, there are also several notable drawbacks, which aredescribed below.

Drawback One: there is no strong force that helps eject the first liquidchemical solution 214 (e.g., the glycerine solution) from the flexiblecontainer 212. Indeed, in a typical implementation, some or most of thatsolution 214 remains in the flexible container 212 regardless of thenature of the hole created by the piercing element 218.

Drawback Two: the flexible container 212 is sometimes, or often,flexible enough to close around the piercing element 218 and effectivelyclose (i.e., prevent flow through) the hole in the flexible container212 created by the piercing element 218.

Drawback Three: the flexible container 212, in some instances, can sealagainst the base of the heater, effectively preventing or inhibiting thefirst liquid chemical reactant's 214 escape from the flexible container212 into the second liquid chemical reactant 216.

Drawback Four: even if the other problems mentioned herein were solvedor their deleterious effects minimized, the single hole in the flexiblecontainer 212 can be expected to discharge the first liquid chemicalreactant into only a small portion of the reaction chamber, so that onlya limited portion of the chemicals react, and, as a result, the heatermodule 204 will produce an inadequate amount of heat to satisfy itsintended purpose.

Drawback Five: since the piercing element 218 crosses the boundarybetween the outside and inside of the heater module 204 housing 207, aleakage path exists, or may easily form, around the shaft of thepiercing element 218.

FIG. 3 is a schematic, cross-sectional view of a container 300 thatdetails another way of implementing the self-heating container 100 inFIG. 1; FIG. 4 is a close-up view showing part of the FIG. 3 container300. The container 300 in FIG. 3 and in FIG. 4 is, in some ways, similarto the container 200 in FIG. 2. As discussed herein, however, thecontainer 300 in FIG. 3 is able to overcome or at least mitigate one ormore (or all) of the above-mentioned, and perhaps other, drawbacksassociated with the container 200 in FIG. 2.

The container 300 in FIG. 3 has a storage compartment 302 containingproduct to be heated (e.g., cheese 306 that will melt onto and mix withnachos). In a typical implementation, the material to be heated (in thiscase cheese dip) would be sealed inside the storage compartment 302 by aremovable seal (not shown).

A heater module 304 is physically and thermally coupled to the storagecompartment 302 and is configured to produce heat when activated forheating at least the cheese in the storage compartment 302. The heatermodule 304 has a housing 307 that defines a reaction chamber. In thisregard, the reaction chamber has multiple walls, at least one of whichis in direct physical contact with and thermally coupled to the storagecompartment 302.

There is a first liquid chemical reactant 314 (e.g., potassiumpermanganate solution) inside the reaction chamber, and a flexiblecontainer 312 (e.g., a plastic bag) inside the reaction chamber, andimmersed in the first liquid chemical reactant 314. There is a secondliquid chemical reactant 316 (e.g., a glycerine solution) inside theflexible container 312. The second liquid reactant 316 is configured toreact exothermically with the first chemical reactant 314 upon contact.

There is a rigid barrier 322 inside the reaction chamber that defines afirst portion 324 of the reaction chamber from a second portion 326 ofthe reaction chamber. Generally speaking, in the illustratedimplementation, the first portion 324 of the reaction chamber includesthe area above the rigid barrier 322, and the second portion 326 of thereaction chamber includes the area below the rigid barrier 322. Thereare fluid communications portals that fluidly connect the first portion324 of the reaction chamber to the second portion 326 of the reactionchamber. The term reaction chamber should be construed broadly toinclude any section(s) of the heater module 304 (e.g., in the firstportion 322 of the reaction chamber, the second portion 326 of thereaction chamber, or elsewhere) where any portion of the first liquidchemical reactant 314 or second liquid chemical reactant might becontained and/or react during normal system heating operations.

The rigid barrier 322 may be any one of a variety of possible shapes andmay define the first portion 324 of the reaction chamber and the secondportion 326 of the reaction chamber to have any one of many possibledifferent physical configurations. However, generally speaking, therigid barrier 322 defines separate portions of the reaction chamber—thefirst portion 324 that physically accommodates the flexible container312, and the second portion 326 that is physically separate from thefirst portion 324 during all phases of system operation and thatgenerally does not include any part of the flexible container 312 duringany phase of system operation. As discussed in further detail herein,the second portion 326 of the reaction chamber provides a clearlydefined, unobscured fluid communication path for the second liquidchemical reactant to freely exit and move clear of the flexiblecontainer 312. In a typical implementation, this fluid communicationpath retains its shape, and remains substantially unobstructed,throughout system operation, even as the flexible container 312 emptiesand, therefore collapses.

The flexible container 312 is positioned atop the rigid barrier 322 inthe illustrated implementation, and is configured so that its outer sideedges are close to, but do not overlap with, the fluid communicationsportals that fluidly connect the first portion 324 of the reactionchamber to the second portion 326 of the reaction chamber.

There is a spring-loaded movable platform 328 at an opposite side of theflexible container 312 from the rigid barrier. The movable platform 328in the illustrated implementation is configured to move in a downwarddirection (i.e., toward the flexible container 312) to help initiateheating and ensure thorough mixing of the liquid chemical reactants 314,316. The movable platform 328 is in direct physical contact with theflexible container 312 and, therefore, any downward motion, such asmight occur when the flexible container 312 is ruptured by a piercingelement, will tend to collapse and help empty the flexible container312. In a typical implementation, the movable platform 328 is largeenough to cover all or at least a very substantial portion of theflexible container 312.

There is a spring 330 at an opposite side of the movable platform 328from the flexible container 312. The spring 330 in the illustratedimplementation is in direct physical contact with the movable platformand with the upper wall (i.e., the heat transfer surface) of thereaction chamber. In a typical implementation, before the flexiblecontainer has been pierced, the spring 330 is in a highly compressedstate and is urging the movable platform 328 in a downward direction(i.e., toward the flexible container 312).

Once the flexible container 312 is pierced, the spring 330 begins toextend, thereby causing the movable platform 328 to move in directionthat helps to collapse the flexible container 312 (i.e., downward inFIG. 3), thereby encouraging the second liquid reactant 316 to exit theflexible container 312 and travel through fluid communication pathsand/or channels defined by the rigid barrier 322 after the flexiblecontainer has been pierced.

The spring 330 is typically configured so that it can move the movableplatform 328 from its position (as shown in FIG. 3) atop the full andcompletely intact flexible container 312 all the way down to a positionwhere it is pressing the fully deflated (and emptied) flexible containerflat against the rigid barrier 322, so that only the fully deflated (andemptied) flexible container 312 remains between the movable platform 328and the rigid barrier 322.

In some implementations, prior to heater activation (e.g., in theconfiguration shown in FIG. 3), the spring-loaded platform 328 pressesdown on the full and completely intact flexible container 312 to helpkeep the flexible container 312 in place between the movable platform328, and the rigid barrier 322, and positioned so as to not cover any ofthe fluid communications portals that fluidly connect the first portion324 of the reaction chamber to the second portion 326 of the reactionchamber. In some implementations, additional (or other) means may beused to help keep the flexible container 328 in place. These caninclude, for example, the use of an adhesive between the platform 328and the flexible container 312 and/or between the upper surface of therigid barrier 322 and the flexible container 312. Alternatively, thesecan include features formed in the bottom surface of the movableplatform 328 and/or the upper surface of the rigid barrier configured todiscourage sideways motion by the flexible container 312 within thereaction chamber.

The illustrated self-heating system 300 has a piercing element 318(attached to an external activation button 310) configured to pierce theflexible container 312 when the activation button 310 is pressed (i.e.,moved in a direction indicated by arrow “A”). Piercing the flexiblecontainer 312, of course, enables the second liquid chemical reactant216 to exit the flexible container 212 and mix with the first liquidchemical reactant 214.

In some implementations, the self-heating system 300 includes one ormore anti-tamper features (not shown) associated with the activationbutton 310. Generally speaking, an anti-tamper feature may provide orfacilitate tamper resistance, tamper detection, tamper response, and/ortamper evidence. In some applications, the anti-tamper feature(s) areonly tamper-evident. Moreover, in some implementations, the self heatingsystem 300 includes one or more locking features (also not shown) thatcause the activation button (and piercing element 218) to latch or lockinto the depressed (or “heater activated”) position. In thoseimplementations, once the activation button has been pressed (i.e.,moved in the direction of arrow “A” in FIG. 3), the activation button310 and the piercing element 318 become locked in that position.

The activation button 310 is exposed for user manipulation outside thehousing 307 of the reaction chamber. The shaft of the activationbutton/piercing element, therefore, extends essentially through thehousing 307 and into the reaction chamber. In this regard, there is aportion of the piercing element that has a smooth cylindrical outersurface. That portion extends through an opening in the housing 307where there is an elastomeric seal 332 (e.g., an o-ring) between thesmooth cylindrical outer surface of the piercing element and the housing307. The portion of the shaft of the activation button/piercing elementthat has the smooth cylindrical outer surface is long enough, in anaxial direction, that the elastomeric seal remains in contact with andseals against the smooth cylindrical outer surface regardless of thepiercing element's position relative to the housing (e.g., regardless ofwhether the activation button is fully extended or fully depressed).

Referring to the detailed view in FIG. 4, the piercing element 318essentially forms a needle with a cylindrical body that has a pointeddistal tip and a distal portion (at or very near the pointed distal tip)with a fluted external surface that has grooves 336 that extend somedistance along the external surface in a substantially axial direction.Generally speaking, a piercing element 318 can have one or more grooves336. In a typical implementation, the grooves 336 will be evenly spacedfrom one another about a perimeter of the otherwise cylindrical piercingelement shaft.

The illustration shows two fluid distribution channels (338 a, 338 b) inthe second portion 326 of the reaction chamber (i.e., the portion of thereaction chamber beneath the rigid barrier 322). Each of the illustratedfluid distribution channels (338 a, 338 b) extends from the roughlycentrally located piercing element 318 outward in a substantially radialdirection. Moreover, these fluid distribution channels 338 a, 338 bextend in approximately opposite directions from the roughly centrallylocated piercing element 318. Each fluid distribution channel 338 a, 338b terminates at a respective one of the fluid communications portals 340a, 340 b that fluidly connects its associated fluid distribution channel338 a, or 338 b to a portion of the second portion 326 of the reactionchamber that is away from the flexible container 312. Thus, each fluiddistribution channel 338 a, 338 b (and its associated fluidcommunication portal) is configured to carry some portion of the secondliquid chemical reactant released from the flexible container 312 to asection of the first portion of the reaction chamber away from where theflexible container 312 is located after the flexible container 312 hasbeen ruptured.

In a typical implementation, the piercing element 318 is configured tomove (when the activation button 310 if appropriately manipulated, e.g.,pressed) in an axial direction from a first position, as shown in FIG. 4(entirely outside the flexible container 312) to a second (“activated”)position, as shown in FIG. 5 (extended into the flexible container 312).More particularly, when the piercing element 318 in the second(“activated”) position (FIG. 5), the pointed distal tip 334 of thepiercing element 318 is inside the flexible container 312. Moreover,when the piercing element 318 is in the second (“activated”) position(FIG. 5), the fluted portion of the piercing element shaft extends frominside the flexible container 312, through the rigid barrier 322, and tothe fluid distribution channels 338 a, 338 b in the second portion 326of the reaction chamber (beneath the rigid barrier). Each groove 336 inthe fluted portion of the piercing element shaft is typically wideenough and deep enough to facilitate a relatively easy flow of the firstliquid chemical reactant (e.g., the glycerine solution) out of thecollapsing flexible container 312 and into the fluid distributionchannels 338 a, 338 b.

It is apparent that the fluid distribution channels 338 a, 338 b in theillustrated implementation are configured to carry the second liquidchemical reactant to a section of the first portion of the reactionchamber away from where the flexible container 312 is located so thatthe flexible container 312 is not able to block the second liquidchemical reactant from entering the reaction chamber and mixingsufficiently with the first liquid chemical reactant.

Generally speaking, in one or more implementations of the container inFIG. 3, one or more of the drawbacks mentioned above in connection withthe container of FIG. 2 can be overcome. For example, in someimplementations:

-   -   1. Drawback one may be eliminated, or at least mitigated, by        providing a spring-loaded platform 328 inside the heater module.        In this regard, the spring-loaded platform 328 is generally        configured to squeeze the flexible container 312 and thereby        provide an internal pressure to the flexible container 312. In a        typical implementation, as mentioned above, the stroke of the        spring 330 is long enough to empty all of the fuel out of the        bag. In addition, in some implementations, the flexible        container may be an elastomeric bag under tension, so that the        edges of the bag are pulled into the center, eliminating trapped        volumes in the corners.        -   AND/OR    -   2. Drawback Two may be overcome, or at least mitigated, by using        a piercing element 318 of sufficient diameter to incorporate a        defined flow path (e.g., with the grooves in the fluted portion        of the piercing element shaft), and arranging the piercing        element 318 so that the grooves extend across the membrane of        the flexible container 312 (and into the second portion of the        reaction chamber (beneath the rigid barrier 322) after the        flexible container 312 has been pierced. This flow path can be        formed with a sharp-ended rod that has grooves along its shaft        to provide a flow path across the membrane, as shown, for        example, in FIG. 5. Another alternative piercing element design        is represented in FIG. 6 (discussed below), in which a hollow        tube is provided (instead of a rod with external grooves) to        form a flow path for the first liquid chemical reactant (i.e.,        the activator).        -   AND/OR    -   3. Drawback Three may be overcome, or at least mitigated, by        providing a cavity in the space around the piercing element        which is small enough in diameter and deep enough that the fuel        bag cannot close the flow path. A path or paths lead from the        cavity into the heater enclosure, completing the flow path from        the interior of the fuel bag to the interior of the reaction        chamber.        -   AND/OR    -   4. Drawback Four may be eliminated, or at least mitigated, by        providing radial flow paths (e.g., fluid transmission channels)        to duct the first liquid chemical reactant (e.g., the fuel)        beyond an area of any potential fuel bag (i.e., flexible        container) seal.        -   AND/OR    -   5. Drawback Five may be eliminated, or at least mitigated, by        providing an elastomeric self-sealing gasket (e.g., an o-ring)        around the shaft of the piercing element. This can be placed in        a location beyond the grooves or holes in the piercing element        so that at all times it lies against the smooth barrel of the        piercing element. Generally speaking, since the heater module        itself is at no time substantially pressurized, the maximum        pressure across the seal will never exceed the sealing        capabilities of the seal.

FIG. 6 is a partial, schematic, cross-sectional side view of aself-heating container 600 design that is similar in many respects tothe self-heating container 300 shown in FIG. 3 and discussed hereinabove. The piercing element 618 in the container 600 of FIG. 6, however,is different than the piercing element 318 in the container 300 of FIG.6. More particularly, the piercing element 618 in FIG. 6 essentiallyforms a needle with a hollow tubular body with an opening at or near apointed distal end thereof and one or more openings in a sidewallthereof. Fluid can flow into the opening at or near the pointed distalend of the piercing element 618, through the hollow tubular body in anaxial direction, and out through the one or more sidewall openings toescape the flexible container 312.

FIG. 7 is a perspective, partial cut-away view of an exemplarydistribution manifold 722 that may define fluid communication paths forthe first liquid chemical reactant (e.g., the activator). Theillustrated manifold is formed in a base 734 (i.e., a lower surface) ofa heater module (e.g., 304). It includes a piercer hole 728, a plenum730 and six slots 732 (or fluid distribution channels) that extendradially outward from the centrally-disposed plenum 730.

The piercer hole 728 is a substantially cylindrical hole that extendsall the through the base and, in the illustrated implementation, iscentered relative to the substantially cylindrical concentric plenum730. The plenum 730 is larger than the piercer hole 728 and extends onlypartially through the base. The slots 732 also extend only partiallythrough the base.

The figure shows a dashed line that shows the limit of where theactivator bag (i.e., the flexible container) can cover. Notably, theouter, distal edges of the slots extend beyond that limit. This helpsensure that, during operation, the activator bag will not be able toblock any fluid flow paths through the slots 732.

In some implementations, the distribution manifold is formed directly ina bottom surface of the heater module. In these implementations, thepiercer hole may be drilled through the base, the plenum may bepartially drilled into an upper surface (i.e., facing the reactionchamber) of the base and the slots may be similarly partially drilled oretched into the upper surface of the base. In other implementations, thedistribution manifold may be a separate piece that is attached to theheater module.

FIG. 8A is an exploded view showing part of an alternative heater modulearrangement. According to the illustrated alternative, the heater moduleincludes a piston and cylinder assembly in lieu of the container andspring-loaded platform in FIG. 3, for example.

More particularly, the illustrated implementation includes a cylinder858 and a piston 850 with a cup seal that is sized to move up and downinside the cylinder 858. There is a spring 852 above the piston 852 thatgets compressed, when assembled, between the piston 850 and a ventedbase cover 854 at the top of the cylinder. There is a membrane 860 thatseals the bottom of the cylinder and one of the reactants would beinside the cylinder until the heater is activated. In a typicalimplementation, the vented base cover prevents a vacuum from formingbehind the piston as it moves down through the cylinder.

There is a distribution manifold 862 below the cylinder 858. Thedistribution manifold 862 includes a hole 864 to accommodate a piercingelement, a plenum 866 and a plurality of holes (or fluid distributionchannels) 868 that extend in a radially outward direction from theplenum 866. The piercing element is configured to extend through thehole 864 and pierce the membrane 860 to initiate heating.

FIG. 8B is an exploded view showing part of an alternative heater modulearrangement. The arrangement in FIG. 8B is similar to the arrangement inFIG. 8A. However, the arrangement in FIG. 8B includes an air bag 856 tourge the piston in a downward direction instead of a spring.

Trials of an exemplary heater activation system have shown that it workswell. As an example, FIG. 9 presents a graph of the temperature historyof a particular test. Shown are the temperatures of the heater andtarget. In this case, the substance being heated is milk chocolate.

A number of embodiments of the invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention.

For example, the specific size, shape and relative arrangement ofcomponents can vary considerably. Various different materials andchemicals may be used for the different components.

The first liquid chemical reactant (e.g., the activator) is preferablyin a bag. However, the bag may be replaced by a syringe-type of rigidcontainer, or other type of container. Either chemical reactant can beprovided in the bag, with the other outside the bag.

An activation button is pressed to initiate heating. However, theactivation element can be virtually any kind of activation elementincluding, for example, a knob, a switch, etc.

Likewise, the spring may be replaced by an airbag or the like.

The heating concepts can be applied to a wide variety of heatingapplications.

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of anyinventions or of what may be claimed, but rather as descriptions offeatures specific to particular embodiments of particular inventions.Certain features that are described in this specification in the contextof separate embodiments can also be implemented in combination in asingle embodiment. Conversely, various features that are described inthe context of a single embodiment can also be implemented in multipleembodiments separately or in any suitable subcombination. Moreover,although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, the separation of various system components in theembodiments described above should not be understood as requiring suchseparation in all embodiments, and it should be understood that thedescribed program components and systems can generally be integratedtogether in a single product or packaged into multiple products.

It should be understood that relative terminology used herein, such as“upper”, “lower”, “above”, “below”, “beneath”, etc. is solely for thepurposes of clarity and is not intended to limit the scope of what isdescribed here to require particular positions and/or orientations.Accordingly, such relative terminology should not be construed to limitthe scope of the present application. Additionally, the termsubstantially, and similar words, such as substantial, are used herein.Unless otherwise indicated, substantially, and similar words, should beconstrued broadly to include both completely and almost completely.

Other implementations are within the scope of the claims.

What is claimed is:
 1. An apparatus for heating a product, the apparatuscomprising: a housing that defines a reaction chamber; a rigid barrierinside the reaction chamber that divides the reaction chamber into afirst portion of the reaction chamber above the rigid barrier and asecond portion of the reaction chamber below the rigid barrier; a firstliquid chemical reactant inside the first portion of the reactionchamber and the second portion of the reaction chamber; an intactflexible bag inside the first portion of the reaction chamber, restingon an upper surface of the rigid barrier, and immersed in the firstliquid chemical reactant, a second liquid chemical reactant within theflexible bag, wherein the second liquid chemical reactant is configuredto react exothermically with the first chemical reactant upon contact; apiercing element that is movable to pierce a lower surface of theflexible bag and to help define a fluid communication path from insidethe flexible bag to the second portion of the reaction chamber when adistal end of the piercing element is extended into the flexible bag;and one or more fluid distribution channels in the second portion of thereaction chamber configured to carry the second liquid chemical reactantfrom the fluid communication path to a section of the first portion ofthe reaction chamber away from where the flexible container is located.2. The apparatus of claim 1, further comprising: a platform configuredto contact the container at an opposite side of the flexible containerfrom the piercing element.
 3. The apparatus of claim 2, furthercomprising: a spring or airbag configured to urge the platform indirection that tends to collapse the container after the piercingelement has pierced the container, thereby encouraging the secondreactant to exit the flexible container, travel through the fluidcommunication path and the one or more fluid distribution channels afterthe flexible container has been pierced.
 4. The apparatus of claim 1,wherein the piercing element comprises: a needle with a hollow tubularbody having an opening at or near a distal end thereof, wherein theopening connects to a fluid path that extends axially though at leastpart of the needle, and one or more openings in a sidewall of the needlealong the fluid path, or a needle having a cylindrical body with adistal portion thereof having a fluted external surface.
 5. Theapparatus of claim 4, further comprising: an activation button exposedoutside the housing and connected to a proximal end of the piercingelement.
 6. The apparatus of claim 5, wherein the piercing element has asmooth cylindrical outer surface between either the one or more openingsin the sidewall or the fluted external surface, and the activationbutton.
 7. The apparatus of claim 6, wherein a portion of the piercingelement that has the smooth cylindrical outer surface extends through anopening in the housing, the apparatus further comprising: an elastomericseal between the smooth cylindrical outer surface of the piercingelement, wherein the smooth cylindrical outer surface is axially longenough that the elastomeric seal remains in contact with and sealsagainst the smooth cylindrical outer surface regardless of the piercingelement's position relative to the housing.
 8. The apparatus of claim 1,wherein the one or more fluid distribution channels comprise multiplefluid distribution channels, and wherein each of the fluid distributionchannels extends from the piercing element in an outward radialdirection that is different than the others, wherein each of the outwardradial directions is perpendicular to a direction that the piercingelement moves to pierce the flexible bag.
 9. The apparatus of claim 1,wherein the flexible bag is a plastic bag.
 10. The apparatus of claim 1,wherein a first one of the liquid chemical reactant and the secondliquid chemical reactant comprises a potassium permanganate solution andwherein a second one of the liquid chemical reactant and the secondliquid chemical reactant comprises a glycerine solution.
 11. Theapparatus of claim 1, further comprising: a storage compartment for afood substance or some other substance to be heated, wherein at leastone wall of the storage compartment is in direct physical contact withand thermally coupled to the reaction chamber.
 12. The apparatus ofclaim 11, further comprising a meltable substance in the storagecompartment, wherein, upon heating, the meltable substance melts and atleast partially mixes with and/or covers the food or other substance tobe heated in the storage compartment.
 13. The apparatus of claim 1,wherein the one or more fluid distribution channels are configured tocarry the second liquid chemical reactant to a section of the firstportion of the reaction chamber away from where the flexible containeris located so that the flexible container is not able to block thesecond liquid chemical reactant from entering the reaction chamber andmixing sufficiently with the first liquid chemical reactant.
 14. Theapparatus of claim 1, wherein the piercing element is configured topierce the lower surface of the flexible bag at a position on the lowersurface of the flexible bag that is surrounded by portions of the lowersurface of the flexible bag that are resting on and in direct physicalcontact with the rigid barrier, such that those portions of the lowersurface of the flexible bag that are resting on and in direct physicalcontact with the rigid barrier prevent any portions of the second liquidchemical reactant that exit the flexible bag from flowing in between theflexible bag and the rigid barrier.
 15. The apparatus of claim 14,wherein the piercing element creates an opening in the lower surface ofthe flexible bag when the piercing element pierces the lower surface ofthe flexible container, which produces a fluid flow path from theflexible bag to the first portion of the reaction chamber outside theflexible bag, wherein the fluid flow path comprises the opening, thefluid communication path, and the one or more fluid distributionchannels and is unobstructed by the flexible bag's resting on the uppersurface of the rigid barrier.
 16. The apparatus of claim 15 configuredsuch that, once the piercing element has pierced the lower surface ofthe flexible bag, the second liquid chemical reactant can exit theflexible bag through the pierced lower surface of the flexible bag,through the fluid communication path, through the one or more fluiddistribution channels and into the first portion of the reactionchamber, even though the flexible bag is resting on and in directcontact with an upper surface of the rigid barrier.
 17. An apparatus forheating a product, the apparatus comprising: a storage compartmentcontaining one or more products to be heated; and a heater modulephysically and thermally coupled to the storage compartment andconfigured to produce heat, when activated, for heating the one or moreproducts in the storage compartment, wherein the heater modulecomprises: a housing that defines a reaction chamber inside the housing;a rigid barrier inside the reaction chamber that divides the reactionchamber into a first portion of the reaction chamber above the reactionchamber and a second portion of the reaction chamber below the reactionchamber; a first liquid chemical reactant inside the first portion ofthe reaction chamber and the second portion of the reaction chamber; anintact flexible bag inside the first portion of the reaction chamber,resting on an upper surface of the rigid barrier, and immersed in thefirst liquid chemical reactant; a second liquid chemical reactant insidethe flexible bag, wherein the first chemical reactant and the secondchemical reactant are configured to produce an exothermic chemicalreaction when they come into contact with each other; a piercing elementthat is movable, by a user, to pierce a lower surface of the flexiblebag, wherein, after piercing the flexible bag, when a distal end of thepiercing element is inside the flexible bag, the piercing elementestablishes or helps establish a fluid communication path from insidethe flexible bag to the second portion of the reaction chamber; and oneor more fluid distribution channels in the second portion of thereaction chamber in fluid communication with the fluid communicationpath and in fluid communication with a section of the second portion ofthe reaction chamber away from where the flexible bag is located.
 18. Anapparatus for heating a product, the apparatus comprising: a housingthat defines a reaction chamber; a first chemical reactant inside thereaction chamber; an intact flexible bag inside a first portion of thereaction chamber; a second liquid chemical reactant inside the flexiblebag and configured to react exothermically upon contact with the firstliquid chemical reactant; a piercing element that is movable to piercethe flexible container; one or more fluid distribution channels in asecond portion of the reaction chamber, wherein the second portion ofthe reaction chamber is separated from the first portion of the reactionchamber by a rigid barrier, wherein the first chemical reactant is inthe first portion of the reaction chamber and the second portion of thereaction chamber, wherein the intact flexible bag is resting on an uppersurface of the rigid barrier and immersed in the first chemicalreactant, wherein the piercing element is movable to pierce the flexiblecontainer and establish a fluid communication path from inside theflexible container to the one or more fluid communication channels, andwherein the one or more fluid communication channels are configured tocarry the second liquid chemical reactant to a section of the secondportion of the reaction chamber away from where the flexible containeris located.